Not Applicable.
Not Applicable.
1. Field of Invention
This invention relates to a device to allow pets to pass through a structural member such as a wall or a door. More specifically, this invention relates to a door insert flap having a cammed mechanism to provide pet access through a structural member.
2. Description of the Related Art
Pet doors are commonly used to allow a pet ingress or egress through a solid or semi-solid structural member such as a door or a wall. While varying in complexity, the overall goal of a pet door is to provide a controlled ingress and egress through a self-closing opening which is easily operable by a pet, yet has sufficient resistance to prevent opening due to wind and rain or other weather conditions. Prior art pet doors are known to have no locking mechanism and/or no mechanism to resist opening by the wind, or to have a multitude of parts to provide such features, thereby increasing the complexity and cost of such pet doors. Pet owners seek a simple and reliable pet door that can be installed quickly and easily and which allows controlled ingress and egress of a pet from an enclosure.
An example of the prior art is U.S. Pat. No. 5,406,748, issued to Davlantes, which discloses a vertically movable pet door flap apparatus including a frame element having a top frame portion, an opening in the frame enclosure, and a flap element that closes the opening. The flap top portion includes a horizontally extending pivot element for pivotably moving the flap in response to a horizontal force applied by an animal. The flap top portion includes a cam element that rotates the top frame portion during pivotal movement of the flap away from the generally vertical position of the flap. The flap top portion further includes a multi-component horizontally extending pivot means and a rotatable horizontal axial portion for pivotably moving the flap. The cam element is attached to the ends of the flap top portion and includes a cam assembly defining an aperture, a slot in the cam element, and a protrusion such as a flange for engagement with the horizontally extending pivot means. The flap is tapered to be seated within the frame element when closed. The pet door also includes a locking element. The pet door flap apparatus requires a plurality of parts for proper operation of the cam element and cam assembly for opening and closing of the flap.
Therefore, it is an object of the present invention to provide a door flap apparatus to provide ease of entry and exit to an enclosure by an animal without having a multitude of complex parts for operation.
It is another object of the present invention to provide an apparatus with a self-closing door flap that is resistant to opening by wind or rain.
It is another object of the present invention to provide an apparatus with a self-sealing door flap having a cammed apparatus for rotation of the door flap.
It is another object of the present invention to provide a pet door flap apparatus that is manufactured with a minimum of parts.
In accordance with the present invention, there is provided a pet door. The pet door includes a two-piece frame disposed on opposing faces of a door, or other structural member. The frame defines through-opening which bounded by a substantially U-shaped lip which extends through the door and which is closed by a pivotable flap.
The pivotable flap is maintained in a normally substantially closed position by a pair of cams members which terminate a pair of axial extensions defining the pivot axis of the flap along the top horizontal edge. Each cam member rests upon a horizontal shelf defined by the frame lip and defines a forward extent and rearward extent perpendicular to the face of the flap which, together with the weight of the flap, provides the resistive force to return the flap to a normally vertical closed position when undisturbed. Each extent has a bottom edge and front edge which are substantially flat and a rounded coming between the bottom edge and the front edge. The cam members and the flap do not allow incidental forces to overcome the resistance to pivoting, or the moment of inertia of the cam members and the flap. In this manner, the flap remains in a closed position without the need of sealing gaskets or magnetic devices as utilized in prior art pet doors.
The pet door of the present invention further includes a lock mechanism which provides control over the movement of the flap allowing the pet owner to limit ingress and/or egress as desired. The lock mechanism is contained within a lock enclosure which is attached to the frame. Housed within the lock enclosure are a locking tab positioner and a cooperating spring clip. Disposed on each end of the spring clip is one of a pair of locking tabs. The lock mechanism further includes a pair of locking tab recesses defined on opposing faces of the door flap for receiving the locking tabs. The locking tab recesses generally extend to a depth greater than half of the depth of the door flap to allow the locking tabs to independently or simultaneously engage the respective recess to prevent both ingress and egress without the need for movement of the door flap.
The lock mechanism operates by sliding the locking tab positioner within the lock mechanism enclosure. The locking tab positioner includes a fluctuating top surface which defines a series of peaks and valleys configured to cooperate with the locking tabs of the spring clip. The locking tabs are held against the positioner top surface by the downward force of the independent spring arms of the spring clip. The peaks are arranged such that one or both of the locking tabs are raised through the locking tab slots depending upon the relative position of the locking tab positioner within the locking mechanism enclosure. Similarly, the valleys are arranged such that one or both of the locking tabs do not extend through the locking tab slots depending upon the relative position of the locking tab positioner within the locking mechanism enclosure.